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Demystifying Java Platform Security Architecture Demystifying Java Platform Security Architecture Ramesh Nagappan, CISSP [email protected] www.coresecuritypatterns.com Overall Presentation Goal Learn how to get started on using Java Platform and its core Security Mechanisms . • J2SE, J2ME, Java Card, Applets, Java Web start • Java Security Management tools • Securing Java Code from Decompilation www.coresecuritypatterns.com Presentation Outline ¾ Java Platform Security Architecture ¾ Java Applet Security ¾ Java Web Start Security (JNLP Security) ¾ Java Micro Edition (J2ME) Security Architecture ¾ Java Card Security Architecture ¾ Java Platform Security – Key and Certificate Management tools ¾ Securing the Java code from Decompilation www.coresecuritypatterns.com Java Platform Security Architecture www.coresecuritypatterns.com Basics about Java • Java Platform and its Programming language is introduced by Sun Microsystems during late 1995. – Invented by Dr.James Gosling at Sun Microsystems. • Java offers a object-oriented programming and platform- independent application development environment. – Java delivers a architecture neutral, interpreted and executable bytecode. – Java enables delivering portable cross-platform application solutions. – Java applications can be accessed locally or dynamically loaded from a network. – Java applications are capable of running on any device platform • From smartcards to micro-devices, workstations to enterprise servers, mainframes to supercomputers and so on. www.coresecuritypatterns.com Core Java Technologies • Sun Categorized the Java technologies under three key major editions. – Primarily to simplify software development and to support target deployment platform. – Java Standard Edition (also referred to a J2SE or JDK) • Commonly used as Java runtime environment (JRE) for running basic Java applications – Java Enterprise Edition (also referred to as J2EE or Java EE) • Set of standards and API technologies for developing multi-tier business applications. – Java Micro Edition (also referred to as J2ME or Java ME) • Set of standards and API technologies for Java enabled Micro-devices and embedded systems • Java Card is a sub-set of J2ME for supporting smartcards. www.coresecuritypatterns.com Java Security at the High-level • Security has been an integral part of Java technology from day one. – It has been an evolving design goal of the Java community as Java is primarily targeted to network-centric applications. • Java Security Architecture foundation provides a secure execution environment via: – The Java Virtual Machine (JVM) • The JVM defines a secure environment by enforcing stringent security measures for running Java applications – The Java Programming Language • The Java language provides several inherent features that ensures security and integrity of the Java application and its underlying JVM. www.coresecuritypatterns.com Security in Java Virtual Machine • The Java Virtual Machine (JVM) is an abstract computing engine – It resides on the host computer and serves as the execution environment for executing the compiled Java code. – The JVM insulates the Java application from underlying differences of the operating systems, networks and system hardware. • The JVM’s built-in security architecture protects the Java environment from most security breaches. – The JVM security architecture acts as a primary security layer by protecting users and the environment from malicious acts. – The JVM enforces security via configurable policies, access control mechanisms and security extensions. – The JVM also allows users to securely download and execute untrusted Java programs from remote resources and over the network. www.coresecuritypatterns.com Security in Java Language • The Java language is a general-purpose object-oriented programming language – It delivers platform-neutral compiled code that can be executed by a JVM. • The Java language is designed to provide security of the application and its underlying runtime environment. – The Java language assures security of the application at all levels • From the basic Java language constructs to the Java runtime • From the supporting Java class libraries to the Java application – The Java language also offers several inherent features that contributes to the security of the application. www.coresecuritypatterns.com Security features in Java Language • The key security features of the Java language that contributes to the security are: – Java defines all primitives with a specified size and all operations are defined to be executed in a specific order of execution. – Java language provides access control functionality on variables and methods in the object via namespace management for type and procedure. • Ex. public, private, protected, package etc. – Java language does not allow defining or de-referencing pointers. • Programmers cannot misuse or forge a pointer to the memory or create code defining offset points to memory. – Java object encapsulation supports “programming by contract” that allows reuse of the code that has already been tested. – Java is a strongly typed language – During compile time it does extensive type checking for type mismatches. www.coresecuritypatterns.com Security features in Java Language • Continued: – Java allows declaring classes or methods as final. • Helps to protect the code from malicious attacks via creating sub-classes and substituting it for the original class and override methods. – Java Garbage Collection mechanism contributes to security of Java programs • By providing a transparent storage allocation and recovering unused memory without manual intervention. • Ensures program integrity during execution and prevents programmatic access to accidental and incorrect freeing of memory resulting a JVM crash. www.coresecuritypatterns.com Java Platform Built-in Security • Java provides a built-in security architectural foundation as part of the JVM. – Based on configurable policies and domains – Rule based class loading – Signing code via support for cryptography services. – Allows implementing security policies • For protecting/controlling access to resources • Since inception : Java 1.0.x – Java introduced the notion of a Sandbox based security model – Java 1.0.x sandbox security model helps running all Java applications locally within the resources available to the JVM. • Protects downloaded Java applets cannot access or alter the user’s resources beyond the sandbox – Java 1.1.x introduced ‘signed applets’, which allowed downloading and executing applets as trusted code after verifying applet signer’s information. www.coresecuritypatterns.com JDK 1.1 Security Model www.coresecuritypatterns.com Java 2 Platform Security Model • Java 2 Platform (J2SE) introduced significant security enhancements to JDK 1.1.x. – Full-fledged support for cryptographic services – Tools for PKI management and digital certificates – Policy-driven restricted access control to JVM resources – Rule-based class loading and verification of bytecode – Policy driven access to Java applets downloaded by a Web browser • In J2SE Security architecture, all code can be subjected to a ‘Security Policy’ – regardless of running locally or downloaded remotely – All code can be configured to make use of a ‘Protection domain’ (equivalent to a sandbox) and a Security policy. – The Security policy dictates whether the code can be run on a particular protection domain or not. www.coresecuritypatterns.com J2SE Security Architecture Elements www.coresecuritypatterns.com J2SE Protection Domain • J2SE introduced the notion of “Protection Domains” , that allows to enforce access control policies. – Configuring a ‘Protection Domain’ allows grouping of classes and instances by associating them with a “Security policy” containing set of “Permissions”. – Protection domains are determined by the current security policy defined for a Java runtime environment. – The java.security.ProtectionDomain class encapsulates the characteristics of a Protection Domain. – With out defining a Protection Domain - by default all “local” Java applications run unrestricted as trusted applications • Protection Domains are generally categorized as two domains. – System Domain: All protected resources such as file systems, networks – Application Domain: The protected resources that are part of the single execution thread. www.coresecuritypatterns.com Permissions • ‘Permissions’ determine whether access to a resource of the JVM is granted or denied. – Permissions give specified resources or classes running in the instances of the JVM – the ability to permit or deny certain runtime operations. • For example: An applet or application using a Security Manager can obtain access to a system resource only if it has permissions. – The Java Security API defines a hierarchy of Permission classes. – The java.security.Permission is the abstract class that represents access to a target resource. – The Permission class contain several sub-classes to represent different type of permissions. • Example ‘Permission’ Classes – For wildcard permissions: java.security.AllPermission – For network permissions: java.net.SocketPermission – For file system permissions: java.io.FilePermission www.coresecuritypatterns.com Setting Permissions in a policy • ‘Permissions’ can be defined using a security policy configuration file. – If a caller application requires access to a file located in a file system. The caller application must have the permissions granted to access the file object. – For example, to grant access to read a file in “c:\temp”
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